/Engine/Source/Editor/Sequencer/Public/ISequencerModule.h
Get the extensibility manager for add track menus.
Add Track Menu extensibility manager.
[TSharedPtr](API\Runtime\Core\Templates\TSharedPtr)< [FExtensibilityManager](API\Editor\UnrealEd\Toolkits\FExtensibilityManager) > GetAddTrackMenuExtensibilityManager() const